You take fifty oaths and you are entitled to blood-wit of (one) slain among you (or your companion). They said: Messenger of Allah, we neither saw (with our own eyes this murder) nor were we present there. Thereupon (Allah's Messenger is reported to have said): Then the Jews will exonerate themselves by taking fifty oaths. They said: Allah's Messenger, how can we accept the oath of unbelieving people? Bushair said that Allah's Messenger (ﷺ) paid the blood-wit himself.
Sahih Muslim Book 28, Hadith 5